Thermostat.



No. 845,894. PATENTED MAR. 5, 1907 H. E. RBEVE.

THBRMOSTAT.

APPLIUATION FILED FEB. 2, 1906.

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UNITED STATES PATENT OFFICE.

HENRY E. REEVE, OF NEW YORK, N. Y., ASSIGNOR TO AUTOMATIC FIRE ALARM COMPANY, OF NEW YORK, N. Y., A CORPORAITION OF NET V YORK.

THERMOSTAT.

Specification of Letters Patent.

Patented March 5, 1907.

Application filed February 2,1906, Serial N0. 29 9.100.

The object of this invention is to simplify the construction and render it less liable to short circuits or deterioration from any cause, such as corrosion.

The invention consists in improvements the principles of which are illustrated in the accompanying single sheet of drawings.

Briefly, it comprises a casing inclosing the thermostatic device which is insulated, from the casing and in which the leading-in wires are so sealed as to prevent corrosion or short circuits.

Figure 1 is a plan view of a thermostatic device embodying the improvements of my invention. Fig. 2 is a sectional view of the same. Fig. 3 is a View of the interior of the device, the bottom of the casing being removed.

1 indicates the main portion of the casing, which is preferably formed of sheet metal. 2 is the bottom of the casing suitably secured to the body, as by spinning over the rim.

hile the casing performs an exceedingly important function in the completed device as a whole, the parts which constitute the true thermostatic device are the only ones through which current passes. connected together and mounted in the easing, but suitably insulated therefrom.

3 is a cup-shaped metallic member having insulating-disks 4t and 5, preferably of mica, arranged on each side.

6 is a compound bar formed of two metals having different coefficients of expansion. One end of this bar is secured to plate 7.

8 is an adjustable contact-point carried by a plate 9, adjacent the other end of the bar (5.

10 and 11 are plates shaped corresponding to plates 7 and 9 and located above the insulating-disk 4. The plates '7 and t) are located below the insulating-disk o. The

These are parts are held together and electrical connection made between the plates 10 and 7 and 11 and 9, respectively, by rivets or eyelets 12 and 13. The leading-in wires 14 and 15, through which current is adapted to pass, are connected to the plates 10 and 1], preferably by soldering the ends, so that permanent electrical engagement is effected.

16 and 17 are insulating disks, preferably of mica, arranged above and below the plates of the thermostatic device, respectively, for insulating it from the top and bottom of the casing. The upper disk 16 has a passage or passages for the protrusion of turned-up portions of the plates 10 and 11, and the bottom disk 17 has a recess or perforation centered by the boss 18. The outside and bottom of the casing are so formed and spaced apart that the compound bar 6 does not touch either in its expanded or contracted position. hen the temperature device is raised to the predetermined degree, the movable end of the bar 6 engages the contact 8 and complotes the electrical circuit.

Hereto'fore ditliculty has been encrmntered in thermostatic devices caused by corrosion of the parts. This is overcome in my device.

1%) is a collar or tulnllar member, preferably formed integral with the body of the casing and surroumling the junction of the le ad in g-i n wires.

20 is a cap or collar, preferably formed separate, but adapted to be fitted onto the collar and be brazed or soldered thereto. This cap and collar form a chamber which has passages in the form herein shown through the sides of the cap for the lead ing-in wires.

21 and 22 are cup-like extensions arranged around these lateral ope1'iings,\\'hich are preferably provided and 'lilled with suitable material which is not affected by hea- 25 indicates a body of suitable insulating material, which is preferably introdimerl into the chamber in a melted condition by pouring it in through an opening in the top of the cap. by this insulating material when it solidifies. By this means the space between. the plates 10 and 11 and the space within the chamber of the collar s1 rrounding the leading-in wires is tilled solid with material which prevents mg the entrance of moisture and prevents shortcircuiting. The importance of these leatures will be appreciated. by those skilled 111 The o )enin in the to) is closed onlv 10 l e l this art and acquainted with the practical utilities of such a device.

WVhat I claim is 1. In a thermostatic device, a casing, ter' minal plates contained therein, means connected thereto for automatically ei'l'ecting the circuit upon change of temperature, and a chamber adjacent the terminal plates to which the leading-in wires pass, and insulating material filling and closing said chamber.

2. In a thermostatic device, a casing, automatic short-circuiting mechanism contained therein, a chamber having entrance-passages for the leadingin wires, cups surround.- ing the passages,.and insulating material contained within said cups and said chamber.

3. A thermostatic device comprising a casing, automatic short-circuiting mechanism contained therein, a metallic disk centered in said casing, insulating-disks on each side thereof, two terminal plates mounted above one disk, and two plates for the shortcircuiting mechanism mounted below the other disk, rivets connecting the respective plates, conducting-wires attached to the terminal plates, and means for sealing the ends of said wires into said casing and preventing the entrance of moisture.

4. In a thermostatic device, a casing, a metallic disk, a pair of terminal plates, a pair oi supporting-plates, a compound bar havin g one end secured to one supporting-plate, an adjusting-contact carried by the other supporting-plate adjacent the opposite end oi said bar, means for connecting corresponding terminal and supporting plates, and means for insulating said terminal and. supporting plates from said metallic disk and from said casing.

A thermostatic device comprising a easing, an insulating-disk centered and supported by the bottom oi the casing, an automatic circuit-closing mechanism supported above said. disk, terminal plates, electrical means of connection between said plates and said circuit-closing device, and insulating material for scaling in said terminal plates to prevent the entrance of moisture.

6. In a thermostat, a metallic disk, an insulating-disk on each side thereol", 'lour plates, two situated beyond. each disk, rivets for securing said plates and disks together and forming a rigid body, means for automatically e'l'lecti'ng the current through said plates upon changes of temperature and an impertorate casing surrounding and inclosing said parts.

7. A thermostat comprising a casing having top and bottom portions, a metallic disk, two supporting-plates, rigidly secured to but insulated from said disk, a curved bar carried by one plate and. susceptible to changes oi temperature, a stationary contact carried by the other plate and disks of insulating m aterial spacing said metallicdisks and. said plates from the top and bottom portions of the easing, and means for centering the parts in said casing.

8. A thermostat comprising a metallic disk, a pair of terminal plates arranged on one side thereof but insulated therefrom, a pair oi supporting-plates, cm'respomling to said terminal plates, arranged on the other side of said disk but insulated therefrom, means for securing the wrresponding terminals and supporting-plates to said disk and electrically connecting them to each other, and parts carried by said sumaorting-plates adapted to change the conditions in an electric circuit upon change in thermal conditions. 

